The well known shuttle embroidery machine includes a common embroidery frame upon which is mounted four tubes or goods rollers arranged in two sets, one pair over the other. Each of the pairs includes a supply tube upon which there is wound a supply of material or cloth to be embroidered and a rewind tube upon which the embroidered material is wound, the material being stretched between the tube during the embroidering operation. The embroidery frame is shiftable both vertically and horizontally such that the material may be displaced in a complex path determined by the automatic control for the machine. Tke embroidery mechanisms are arranged at relatively stationary locations in relation to the respective pairs and each includes a needle rail at the needle side of the material having a series of needles fixed at spaced locations along the length thereof each of which is fed from a supply of needle thread. A shuttle box rail is provided at the shuttle side of the material which carries a series of longitudinally spaced shuttle boxes corresponding to the needles. The shuttle boxes contain shuttles having bobbins therein providing the supply of shuttle thread for the respective needle threads. Further, at the needle side of the material there is provided a borer point rail which is provided at spaced locations along its length with a number of borer points which, at prescribed intervals during the machine operation, are effective to cut holes in the cloth. Mechanisms are provided for driving the needle rail through a stitch-forming stroke such that the needle threads are passed through the material and form loops through which the respective shuttles are passed causing the shuttle thread to loop through the needle threads, as is generally understood. For certain patterns the borer point rail is operated during the machine cycle to cut the material, and in such instances the holes so cut are bound by the action of the cooperating needles and shuttles.
The needle thread is fed to the respective needles over a yarn tensioning and controlling system which includes, in succession from the supply of the needle thread, a short stroke thread carrier and a long stroke thread carrier. The short and long stroke thread carriers are effective as the needles move through the forward or stitch-forming strokes to initially deliver the needle threads substantially free of tension, to then form a loop through which the shuttle pass as the needles being to retract, and finally to pull back on the needle thread to complete the stitches.
It is generally known to coordinate the various actuating and controlling mechanisms of the shuttle embroidery machine from a common automat. The automat is generally characterized as including a continuous roll of paper or similar material, known as a punching or control tape, which is punched at longitudinal spaced locations and in a number of side by side rows in accordance with the several control functions which are to be sensed and directed to the actuating mechanisms of the embroidery machine. The control functions are sensed through the holes in the punching and mechanically establish the control function in the order in which they are read out of the punching. The punching or control tape indexes for each stitch thereby providing a continuous read-out of control information to the embroidery machine.
It is known, for example from U.S. Pat. No. 3,390,650 ('650), that an attachment may be useful for the application of sequins. Embroidery includes embellishment of cloth with sequins. Sequins are usually circular, shiny discs applied to garmets to increase the appeal and attractiveness of the garment. Sequins produced and applied by the prior art are subject to both deformation and flaking. In the deformed sequin, rather than the desired circular diameter, the sequin cut from the sequin strip has, for example, additional material at noon and material removed at six o'clock. See, for example, the "pit and mound" sequin shown in FIG. 7. This deformation is caused by imprecise contact of the two cutting edges between which edges each sequin is severed. Flaking can also occur when the strip is severed. Additionally in colored sequins, which are lacquered to provide sequins of various colors, this flaking is particularly noticeable. Sequins are embroidered onto cloth for decorative purposes, therefore flaking and deformation of sequins reduces the decorative value.
The '650 patent teaches a moveable cutter 70 which is brought, by the cutter-activating mechanism 82 on the needle rail, into alignment with the stationary cutter blade 66 to sever the leading sequin from a strip of sequins. The cutter 70 is substantially the width of the guide 64 which receives the sequins. Whenever the advancement of the sequin strip is not precise, this cutter 70 will sever a deformed sequin. The imprecise advancement has various causes, some of which are described below.
The '650 patent teaches a feed wheel 74 having sprockets 76 extending radially from the periphery thereof, another source of deformity of the sequins. These strockets typically wear and become thinner. The sequin strip, which is advanced via the strockets, is allowed more play both along the length of the strip and side-to-side within the guide 64, thereby allowing the sequins to be offset from the desired position for severing.
Each of the needle channels on the needle rail wear unevenly at a separate rate depending on the amount of use of each needle. Various embroidery patterns will utilize, for example, every other needle or every third needle thereby causing wear of only the needle channels of the utilized needles. This uneven wear affects the severing of the sequin, resulting in deformity and/or flaking, since the prior art does not allow for horizontal adjustment of each sequin attachment individually to compensate for the wear of the needle channel, but only for the adjustment of banks of sequin attachments. This results in some needles, corresponding to a sequin attachment, passing through the sequin at some location other than directly through the hole thereby damaging the sequin.
In the prior art the base plate, including the guide, is typically substantially heat treated steel. The end of the guide, which is the cutter blade, wears upon continual contact with the cutter, resulting in deformed and/or flaking sequins. A worn cutter blade requires replacement of the entire base plate.
The '650 patent provides for an upstanding base plate 60, of right angle constructon, which includes a vertically extending mounting section 62, which section 62 is provided with a vertically extending guide or chute 64 of a width to receive the strip of sequins. This guide 64 is an integral part of the base plate 60; the spacing between guides 64 cannot be altered without replacing the entire base plate 60. This lack of spacing alteration is an important limitation due to uneven wear of the needle channels.
Many portions of the feeding mechanism 56 including the clamp member 68, moveable cutter 70, and retaining string 80 are secured by rivets, bolts or the like to face plate 60. Replacing broken or worn parts also requires removing the entire base plate 60.
It is known to run conventional embroidery machines with sequin attachments at up to 100 revolutions per minute, which is 100 strokes or 50 stitches of a needle, where two strokes comprise a stitch. Any faster speed results in an unacceptable increase in embroidery errors, which material must either be discarded or repaired by hand, greatly increasing the cost of the overall operation.